The helicopter is a complex aircraft. It must be kept under constant positive control during flight. The principal flight surfaces are an overhead rotor and a vertical tail rotor. The blades of the overhead rotor are of variable pitch, the pitch being controllable to provide the desired lift, rate of ascent or descent and/or air speed. The blades of the overhead rotor rotate in a generally horizontal plane. However, the angle of the entire overhead rotor blades assembly with respect to its horizontal axis and 360.degree. about its vertical axis is variable and controllable to provide pitch, roll and horizontal flight direction control. Generally, the angle of the overhead rotor assembly with respect to its horizontal axis can be varied from 0.degree. to about 10.degree..
The tail rotor blades rotate in a generally vertical plane and are also of controllable variable pitch. Controlling the pitch of the tail rotor blades controls the yaw of the aircraft. Actually, horizontal directional control requires an appropriate coordinated control of the angle of the overhead rotor and the pitch of the tail rotor blades.
Normally, a single engine provides the power to rotate the overhead rotor and tail rotors, which operate at a constant speed when in flight. Engine power is controlled by means of a hand operated throttle; in some aircraft, in combination with a governor.
The proper and safe flight of a helicopter requires constant and coordinated attention to the above mentioned controls. This requires that, when in flight, the pilot must operate individual controls by each hand and each foot and in proper coordination with each other. This coordination of control operation is the most difficult and dangerous aspect of learning to fly a helicopter. Accidents or incidents during helicopter pilot training are, unfortunately, undesirably frequent.
This problem has long been recognized in the art and various methods and schemes have been suggested to provide a means of mastering the required coordination of controls under simulated conditions, avoiding the use of actual helicopters for in-flight instruction in the early stages of the learning process. Devices of the prior art include those disclosed in U.S. Pat. No. 2,711,594, U.S. Pat. No. 4,120,099, U.S. Pat. No. 2,916,832, U.S. Pat. No. 3,225,458, and U.S. Pat. No. 2,958,141. From the standpoint of the instant invention, the most pertinent device is that disclosed in U.S. Pat. No. 3,548,518.
That patent discloses the use of an electrically powered and controlled flying model of a helicopter. The flight controls are electrically operated by the operation of a standard set of full size helicopter controls. In this case, the scale model of the helicopter is tethered, severly restricting the comprehensiveness of flight conditions requiring student pilot response. Furthermore, student errors in flight control are intentionally forgiving making it somewhat difficult for the student to recognize and learn from an error. Somewhat subtle problems in flight conditions and control could no unnoticed.
It is an object of this invention to provide an improved helicopter training device. Other objects will become apparent from the description of this invention.